Cut-off tool



y 27, 1958 A. NUDING 2,836,240

CUT-OFF YTOOL Filed June 9, 1955 INVENTOR. A -ro- A/uazlvs.

United States Patent 6 CUT-OFF TOOL Anton Nuding, Emmaus, Pa., assignor to General Machine Company, Inc., Emmaus, Pa., a corporation of Pennsyivania Application June 9, 1955, Serial No. 514,269

7 Claims. (Cl. 164-36) The present invention relates to machine tools and more particularly to a cut-ofi tool for severing bar or tube stock, such as carbon steel or the like.

In tools of the character to which the invention relates it has been proposed, heretofore, to employ straight shank cutters in many instances, or insert bits in other instances, both of which have fundamental disadvantages. A primary objection to a bit or cutter projecting from, or part of a holder, is that it is unsupported in the vertical piane passing through the cutting edge so that chatter or vibration takes place. Where insert bits are used as an integral part of the tool any damage renders the entire tool worthless and it has to be replaced.

An object of the present invention is to provide a cutoff tool for cutting through rotating bar stock wherein the disadvantages of such prior tools are overcome.

Another object is to provide a cut-off tool wherein the cutting bit has a base below and in vertical alinernent with the bit as a means for absorbing stresses downwardly upon the bit.

Another object is to provide a cut-off tool wherein the usual vibrations developing in the use of such tools are eliminated or substantially reduced.

A further object is to provide a novel removable supporting blade for a bit whereby bits can be repaired or replaced without losing a complete tool. Further objects will appear hereinafter.

in the accompanying drawings Figure 1 is a perspective view of a out 01f tool of the invention showing one side of the tool: Figure 2 is a like view showing the opposite side of the tool: Figure 3 is a perspective view of the holder with the tool blade removed: Figure 4 is a section on line 44 of Figure 2: Figure 5 is a perspective view of a detached blade showing the scarfed anchoring edges: and Figure 6 is a fragmentary elevation of the tool in operative relation to the stock.

Referring to the drawings, one form of cutting tool of the invention is shown comprising a cutting bit 10, preferably of the carbide type, mounted as a permanent insert at the other corner of a supporting blade 11 with its cutting edge 12 lying substantially in the plane of the edge of the blade 11. a fiat top ground into a cutting edge 12, but the invention is not limited to this particular construction as other cutting edges can serve the purpose, for example bevelled type of edge.

The blade 11 is, preferably, rectangular in shape and of a thickness such as to provide a rugged support for the bit it capable of resisting vibration during a cutting operation. As a further guard against vibration, the bottom and rear edge of the blade 11 are bevelled to form a solid interlock with the tool part when attached thereto as will be explained. As shown, the bevel 13 has an angular cut suihcient to resist lateral stresses and illustratively forty-five degree cut has been found practical.

As support for the blade i1, holder is provided As here shown, the bit has Z,$36,Z40 Patented May 27, 1958 ice having a base 14 forming an integral extension of a shank 15, this later serving as a means to mount the tool in the post of a lathe, or the like. The base 14 is formed with an arcuate top face 16 developed on a radius approximately including the bit 10, such face thereby providing a cut-out permitting the stock to ride freely therein during a cut-off operation. Further it should be noted that the base 14 is of substantial thickness capable of absorbing stresses ordinarily causing vibration. An L- shaped recess 17 is formed in one side of the base 14, forming an angular seat conforming to the configuration of the meeting edges of the bottom and one side of the blade 11. The recess 17 provides a relatively wide vertical plane surface 18 to firmly brace the blade in vertical position while its iateraily off-set ledge 20 is bevelled throughout its length complementally to the bevelled edge 13 of the blade 11, so that the latter seats firmly in the recess where assembled for use. The blade 11 is rigidly secured to the side of the base 14 by providing holes 21 in the blade 11 for the respective passage of screws 22 entering tapped holes 23 in the base 14. The matching rows of holes 21 and 23 are arranged to conform to the curvature of the face 16 to thereby most effectively resist radial thrust from the bit 10 while cutting. This relatively wide support face and the interlocking bevels reduce vibration to a negligible minimum. The solid base 14 projecting below and in substantial alinement with the bit lil, makes it possible to perform a cutting operation at unusually high speeds without vibration. Furthermore this overall stiffness built into the tool prolongs the life of the bit, saves resharpening time with consequent reduction in the cost of operations.

it will now be apparent that a complete unitary tool has been devised for efiectively severing bar and tube stock while compensating for vertical and lateral stresses which, heretofore have presented a problem because of the development of vibrations. Also it should be understood that the construction shown is an example of one form of the invention and is not limited to a base specifically in exact vertical alinement with the bit because variations thereof can be made Without departing from the spirit of the invention. Further while the recess 17 is shown on the left side of the base it is possibleand sometimes advantageous to have the recess 17 on the opposite side to permit cutting off the work when turning in the opposite direction. While the preferred shape of the blade 11 is rectangular the invention is not to be limited to this particular configuration.

What is claimed is:

1. A cut-off tool comprising a cutting bit, a blade having two edges forming a notched corner for seating said bit in supported cutting position, said blade also having an angular edge opposite to said corner, a base having a recess in one side complemental to the contour of the said angular edges of said blade as a seat therefor, means to removably attach said blade to said base, said base also having an arcuate face terminating at one end in .alinement with the cutting edge of said bit as a clearance for work being cut, and 'a shank for said base for attachment to a lathe post.

2. A cut-01f tool according to claim 1 wherein means is provided between the blade and the base to resist laterally applied stresses.

3. A cut-on" tool according to claim 2 wherein the re sisting means are bevelled meeting surfaces of the blade edge and the base recess.

4. A cut-01f tool comprising a cutting bit, a rectangular blade supporting said bit in cutting position, a base having a recess in one side complemental to the contour of a portion of the blade to seat said blade against relative movement edgewise, means removably attaching said blade in said recess, and a clearance surface formed on one end of the top of saidtbase developed on "a ra'dius substantially centered at said bit to pass under the'stock being cut, saidsurface terminating at the leading end of the base in the vertical plane of the bit edge of the blade.

t 5. A cut-oil tool, comprising a zsubstantiallytrectangw lar flatiblade; a cutting bit fixedly inserted in an 'up'per' corner thereof, a ba'se'having a'recess opening from one end of :said baseand shaped to seat said blade'against relative movement edgewise, a shank at the other end of i said base for attachment to a lathe post, and means laterally'anchoring said blade seatedin said recess, said base also having an upper marginal arcuate face intersecting'said recess and terminating at its lower end in the plane of the bit end of the blade-when seated, whereby said bit has a'vertically alined support to resist cut ting pressure in all cutting positions. I,

6. A cut-oiftool comprising a base having a top arcuate face" and an angular side recess intersecting siaid face; said recess and face terminating at one end of said base" in a common vertical plane, a'sha'nk on said b a'se': for attachment to a lathe post, a blade complementally contouredto seatin said recessand dimensioned to pro- ,jeet' laterally abovejj-said face 7 as side wallthereoi, and

with a'free edge thereof lying in said vertical plane, and t a cutting rbit attached to the upper end of said freeedge,

whereby said bit has an alined vertical support to'resist working pressure thereon. a

7. A cut-off tool comprising'a cutting bit, a substantially quadrilaterally shaped blade-having two edges meet ing to support said bit in cuttingiposition as an insert, a

basehaving a recess to receive a. portion of said blade 7 It and forming a seat for the blade edges respectively 013-" 2,223,831 Luers Dec. 3, 1940 2,398,913 Anthony et'a'l. Apr. 23,1946 2,658,418 Hoelscher Nov. 10, 1953 May Apr; 27., 1954 Schultheiss'; July 3,1928 7 t 

